How do I keep the table Header at the top while im scrolling down the table

Question

// creating heading for the tables
const tableHead = document.createElement("thead");
for (let prop in eastern[0]) {
  const tableTitles = document.createElement("th");
  tableTitles.innerText = prop;
  tableHead.appendChild(tableTitles);

}

im using javascript in my website i want the table header to stay while the user is scrolling down the table.